题干

铬是人体必需的微量元素,它与脂类代谢有密切联系,能增强人体内胆固醇的分解和排汇,但铬过量会引起污染,危害人类健康。不同价态的铬毒性不同,六价格的毒性最大,几乎是三倍铬毒性的100倍。下列叙述错误的是

A:K2Cr2O7可以氧化乙醇,所以该反应常用于检查酒后驾驶

B:污水中的铬一般为三价铬,但在溶解氧的作用下可被氧化为六价铬

C:发生铬中毒时,可用维生素C缓解性,说明维生素C具有还原性

D:配平Cr2O72-+I-+H+→Cr3++I2+H2O后,Cr3+的化学计量数是4

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D

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    We eat in our cars, at our desks, on the go, and in front of the TV. We eat take-out, packaged and prepared meals. Why? Because it fits our not-enough-time-in-the-day lifestyles____ Well, I'm certainly not the first one to think it—or say it—but we all need to slow down.

    Consumer trends around the globe show that over the past three decades people are purchasing more prepared foods at the grocery and eating out more than ever before. It's predicted that we'll spend more at restaurants in the coming years____However, we're getting less healthy.

    While debates can be seen indifferent media over the food industry's contribution to our growing waistlines and our health problems, the bottom line is this____We can choose to eat a fast-food lunch on the go. We can throw a frozen meal in the microwave and call it dinner. We can eat without thinking, in front of the tube, at our computers, and while driving a car.

    ____Studies have shown meaningful links between family meals and kids' mental and physical well-being. Eating sensibly doesn't take much time or money, but it does require you to make a conscious decision to do so. Wrapped in endless work, appointments and social activities, we often fail to enjoy a relaxing meal with our families.

    While it can be a challenge to always put healthy eating first, just do your best. Remember that the food you eat has a more significant impact on your health, weight and well-being than almost any other activity you do.____ Every meal made at home—even just once or twice a week—is a step closer to a healthier body and as lower food lifestyle.

A. Our food matches our lives.

B. Treat it with the importance that it deserves, but start small.

C. We're consuming an increasing number of calories.

D. Lunch is the biggest calorie intake when it comes to eating out.

E. Purchase food locally and skip as many packaged items as you can.

F. What we eat, where we eat and how we eat are all under our control.

G. We can devote an hour of the day to enjoying a meal with our families.